<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        /* 复合选择器 */
        div.hello{
            color: #f00;
            font-size: 30px;
        }
        h3#abc{
            color: #0f0;
        }
        /* 组合选择器 */
        .world, p, h3#abc{
            text-decoration: underline;
            font-weight: bold;
            background: pink;
        }
        /* 嵌套选择器 */
        /*div span{*/
        div > span{
            background: #ccc;
        }
        /* 伪类选择器 */
        /*a:link{
            color: #000;
            font-size: 13px;
        }
        a:visited{
            color: red;
            font-size: 20px;
        }
        a:hover{
            color: blue;
            font-size: 30px;
        }
        a:active{
            color: green;
            font-size: 40px;
        }*/
        a:link,a:visited{
            color: #333;
            font-size: 15px;
            text-decoration: none;
        }
        a:hover,a:active{
            color: #ff7300;
            text-decoration: underline;
        }

    </style>
</head>
<body>
    <p class="hello">aaa</p>
    <div class="hello">bbb</div>
    <p>ccc</p>
    <h3 id="abc">ddd</h3>
    <div class="world">eee</div>
    <span>222</span>
    <div>
        <span>1111</span>
    </div>
    <div>
        <p>
            <span>333</span>
        </p>
    </div>
    <a href="http://www.sia.com.cn">新浪</a>
</body>
</html>